This invention relates to optical devices, and more particularly to optical waveguide devices.
In the integrated circuit industry, there is a continuing effort to increase device speed and increase device densities. Optical systems are a technology that promise to increase the speed and current density of the circuits. Optical deflectors are optical devices that are configured to perform light deflection. During operation, input light is applied to the optical deflector, and output light exits from the optical deflector deflected by a prescribed angle. One such optical deflector is a trapezoidal prism made from glass or a clear plastic material. Other optical deflectors are made out of semiconductor material, such as silicon. Each optical deflector of different sizes has to be manufactured distinctly. Therefore, the production of precision optical devices is expensive.
Optical deflectors, as with most optical devices, are susceptible to changes in such operating parameters as temperature, device age, device characteristics, contact, pressure, vibration, humidity, etc. As such, the optical deflectors are typically contained in packaging that maintains the conditions under which the optical devices are operating. Providing such packaging is extremely expensive. Even if such packaging is provided, passive optical deflectors may be exposed to slight condition changes. As such, the passive optical deflectors perform differently under the different conditions. For example, the deflectors will deflect the light through a different angle. If the characteristics of a passive optical deflector is altered outside of very close tolerances, then the optical device will not adequately perform its function. In other words, there is no adjustability to the passive optical deflectors.
It is therefore desired to provide an optical deflector whose deflection angle can be adjusted or even nullified to provide varied deflection angles. In another aspect, it is desired to provide an optical deflector that compensates for variations in operating parameters. In another aspect, it is desirable to provide an efficient and economical optical switch including a plurality of optical deflectors.
The present invention is directed to apparatus and associated method for altering the propagation constant of a region of deflecting propagation constant in an optical waveguide. The method comprising positioning an electrode of an electrode shape proximate the waveguide. A region of deflecting propagation constant is projected into the waveguide and corresponds, in shape, to the electrode shape by applying a voltage to the shaped electrode. The propagation constant of the region of deflecting propagation constant is controlled by varying the voltage that adjusts a deflection angle applied to an input optical signal flowing through the waveguide.